Hydroponics Flashcards
What are the benefits of an open system?
There is no need to set up a pump system to re-circulate the nutrient solution (lower cost)
The concentration of nutrients and pH of the solution does not need to be checked as a fresh solution is always used. (less manpower required)
What are the disadvantages of an open system?
The cost of regular replacement of nutrient solution is high
The run-off contaminates the environment as the used nutrient solution can still cause eutrophication in closed water bodies. Processing the run-off is costly
What are the benefits of a closed system?
Recycles nutrient solution as effectively as possible
No contamination of the environment as the solution is re-circulated within the system.
What are the disadvantages of a closed system?
The nutrient solution has to be sampled and analyzed at least once a week to ensure nutrient balance is maintained (labour intensive)
A pump system is needed to re-circulate & oxygenate the nutrient solution (costly)
What is a unique benefit of the Nutrient Film Technique? (Closed System)
Absence of growth medium (e.g Soil) saves cost and makes it easier to check health of roots
What are the disadvantages of the Nutrient Film Technique?
The pump must not fail, as even a short period of the pump not functioning can cause plant death
It is unsuitable for plants with large tap-root systems as the root blocks the flow of nutrient solution down the trough.
What are the advantages of the Deep Flow Technique?
A small change in the nutrient solution’s pH or temperature will not greatly affect the whole solution as it is a large volume of nutrient solution. (buffer)
The rafts which hold the plants can be moved around very easily (less labour intensive)
What is the ideal EC range for hydroponics?
The ideal EC range for hydroponics is between 1.5 to 2.5 dS/m
What is the ideal pH range for hydroponics?
The ideal pH range for hydroponics is between 5.8 to 6.5 dS/m
